In graph A, two waves are shown at a given instant. What is the number of the curve in graph B that represents the wave resulting from the superposition of the two waves in A at this instant?
A) 1
B) 2
C) 3
D) The resultant is zero for all values of x.
E) None of these represent the wave.

Question

In graph A, two waves are shown at a given instant. What is the number of the curve in graph B that represents the wave resulting from the superposition of the two waves in A at this instant?
A) 1 
B) 2 
C) 3 
D) The resultant is zero for all values of x. 
E) None of these represent the wave.

Quizplus · Accepted Answer

At the given instant, the first wave has a positive amplitude and the second wave has a negative amplitude. When they superpose, their amplitudes cancel out and the resultant wave has zero amplitude, as shown by curve 3 in graph B.

In Graph A, Two Waves Are Shown at a Given